Atari 400 User Manual page 72

Now, go ahead-press that mysterious key. It clicks.
but no character appears on the screen, right? And
the cursor didn't move.
SCREEN 1
That's because this is a special key. When you type a
few characters (don't do it yet), you will notice
something different on the screen.
When you press the INVERSE key, the charac-
ters you type will be shown in inverse (blue on
white instead of the normal white on blue) .
Since you've already pressed the INVERSE key,
you're ready to type inverse characters. Type
ATARI COMPUTER
Every character is displayed in
inverse.
SCREEN 2
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